1. Field of the Disclosure
This disclosure relates generally to apparatus and methods for completing a wellbore for the production of hydrocarbons from subsurface formations, including fracturing, gravel packing and flooding selected zones and for communicating information in real-time about various downhole operations.
2. Background of the Art
Wellbores are drilled in subsurface formations for the production of hydrocarbons (oil and gas). Modern wells can extend to great well depths, often more than 6000 meters (about 20,000 ft.). Hydrocarbons are trapped in various traps in the subsurface formations at different depths. Such sections of the formation are referred to as reservoirs or hydrocarbon-bearing formations or zones. Some formations have high mobility, a measure of the ease of the hydrocarbons flow from the reservoir into a well drilled through the reservoir under natural downhole pressures. Other formations possess low mobility and the hydrocarbons trapped therein are unable to move with ease from the reservoir into the well. Stimulation methods are typically employed to improve the mobility of the hydrocarbons through the reservoirs. One such method, referred to as fracturing (also referred to as “fracing” or “fracking”), is often utilized to create cracks in the reservoir to enable the fluid from the formation (formation fluid) to flow from the reservoir into the wellbore. To sand control, frac-pacing and gravel packing multiple zones, an assembly containing an outer string with an inner string therein is run in or deployed in the wellbore. The outer string is conveyed in the wellbore with a tubing attached to its upper end and it includes various devices corresponding to each zone to be fractured for supplying a fluid with proppant to each such zone. The inner string (also referred to as the “service string”) includes devices or tools attached to a tubing (which tubing can extend over 1,000 meters (about 3,000 feet) to perform a number of operations during treatment or service operations, including, but not limited to, setting an upper packer with a packer setting tool, setting a tool at selected locations of the outer string, setting packers, opening and closing valves, flowing fracture fluid from the inner string into the production zones via a frac port, and performing reverse flow and return flow operations. In such systems, It is desirable to obtain real-time information about the various operations performed in a wellbore using the inner string and outer string, including determining location of a device or element downhole, setting a device, fluid flow, temperature and pressure profiles, quality of the performed operations, etc. from various location along the inner string, including locations below the frac port. However, commercially utilized inner strings that include a packer setting tool and frac port are not available with a control line or communication link that runs from the surface to a location below the frac.
The disclosure herein provides systems and methods for use in wellbore operations that include a two-way communication system for providing real-time information between a surface location and downhole devices and operations, including information from locations below the frac port.